Revert "Add instructions for upgrading from V2 to V3 in README (Kines…

…isCorporation#197)"

This reverts commit 2d36945.

README.md

@@ -60,11 +60,6 @@ Follow the programming instruction on page 8 of the [Quick Start Guide](https://
 
 > Note: There are also physical reset buttons on both keyboards which can be used to enter and exit the bootloader mode. Their location is described in section 2.7 on page 9 in the [User Manual](https://kinesis-ergo.com/wp-content/uploads/Advantage360-ZMK-KB360-PRO-Users-Manual-v3-10-23.pdf) and use is described in section 5.9 on page 14. 
 
-### Upgrading from V2 to V3
-
-If you are upgrading from V2 to V3, and if the flashing didn't work as expected (i.e. if you are unable to pair the keyboard via Bluetooth), then consider [resetting](https://kinesis-ergo.com/support/kb360pro/#firmware-updates) both halves of the keyboard to its native state. Make sure to use the `settings-reset.uf2` file from 
-the V3 branch of this repository. After doing this, proceed with the flashing instructions above.
-
 ## Other support
 
 Further support resources can be found on Kinesis.com: